Food vendors are being urged to be on their guard against rogue schools offering distance learning courses.

Spot checks by environmental health officers across Hambleton have uncovered traders with certificates supplied by unknown food hygiene schools - certificates that the district council does not recognise as legal.

All mobile food traders must be qualified to at least the foundation food hygiene levels to operate - giving them the necessary knowledge in handling food safely to ensure it is fit to eat and will not cause illness or even death.

"During our regular spot checks on traders last weekend officers became suspicious of one in particular because the sales assistant did not know how to tell if food was cooked thoroughly and in the case of meat with no trace of blood in the middle.

"On top of that the condition of the cooking area was not up to scratch," said head of environmental health and housing, Eric Kendall.

"When we checked for the food hygiene certificates they had been issued by a school based in Cornwall which has already been the subject of numerous investigations.

"The school has never been assessed by any official food body - groups which require rigorous standards.

"We would urge all our vendors to check that their certificates have been awarded by nationally recognised bodies."